Timber frame exterior insulation / Discussions

What is the best way to insulate the exterior of a post and beam timber frame HOME with rigid insulation?

...exterior with no interior insulation as I wish to keep the bones of the barn exposed internally.  Wall currently has 3/4" Shiplap pine sheathing over the Girts.  Looking at emplacing 4" R20 Rigid XPS Panels seam taped. Those would be strapped to the wall with 7 1/2" screws into the Girts. Board and Batten siding would ...

Posted by Ron Busch Nov. 12, 2021 Wall assemblies - new construction